Thrombopoietin receptor (Mpl) expression by megakaryocytes in myeloproliferative disorders

The thrombopoietin receptor (Mpl) is involved in the pathogenesis of chronic myeloproliferative disorders (CMPD). In this study, we determined Mpl expression by bone marrow cells and megakaryocytes in CMPD by applying laser microdissection, real-time RT-PCR, and immunohistochemistry. Mpl mRNA expression was significantly increased up to 9-fold in total bone marrow cells (p < 0.001) and up to 4-fold in megakaryocytes in chronic myeloproliferative disorders (n = 73) compared to normal controls (n = 26, p = 0.01). Immunohistochemistry revealed heterogeneous Mpl expression by megakaryocytes in CMPD with a stronger accentuation in idiopathic myelofibrosis (IMF) in comparison to polycythaemia vera (PV) and essential thrombocythemia (ET). In addition to megakaryocytes, the erythropoietic lineage was prominently labelled by Mpl antiserum, with considerably stronger staining in polycythaemia vera. We conclude that, in CMPD, megakaryocytes and erythroid cells exhibit increased Mpl expression levels which may contribute to the sustained proliferation of both cell lineages in CMPD.     

The prevalence of metabolic syndrome is increased in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis

Purpose

Cardiovascular disease is one of the major causes of mortality in anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). Metabolic syndrome (MetS) is associated with increased cardiovascular risk in the normal population. However, MetS in AAV has not been adequately investigated. We aimed to determine MetS prevalence and associated factors in AAV patients.

Methods

Thirty-seven AAV patients and 42 healthy controls were enrolled. MetS was determined by International Diabetes Federation (IDF) and National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII) criteria. The relationship between clinical features of AAV and MetS was also investigated.

Results

MetS was significantly higher in AAV patients than controls by NCEP-ATPIII (51.4% vs. 26.2%, p 0.022) and IDF (62.2% vs. 35.7%, p 0.020). When AAV patients with MetS were compared to those without, there were significant differences in age, CRP, GFR and NT-pro-BNP. Age [58 (13) vs. 50 (8) years p: 0.028], CRP [4.0 (3.6) vs. 3.2 (1.0) mg/l, p 0.021] and NT-pro-BNP [173.5 (343.7) vs. 106.0 (103.0) pg/ml, p 0.013] were significantly higher in AAV patients with MetS than those without; GFR was significantly lower [38 (46) vs. 83 (51) ml/min/1.73 m², p 0.004]. ROC curve analysis showed NT-pro-BNP?>?58.0 ng/ml predicted MetS with 87.1% sensitivity and 46.7% specificity (Area under curve: 0.71, CI 0.536–0.902, p 0.041). Multivariate analysis revealed age [OR (95% CI): 1.180 (1.010–1.370), p 0.039] and NT-pro-BNP?>?58 pg/ml [OR (95% CI): 5.5 (1.02–30.1) p 0.047] were independent predictors of MetS in AAV patients.

Conclusion

MetS is significantly higher in AAV patients than controls and is associated with age and NT-pro-BNP. Screening and treating MetS may improve prognosis in AAV patients.

     

Carbamazepine-induced sperm disorders can be associated with the altered expressions of testicular KCNJ11/miR-let-7a and spermatozoal CFTR/miR-27a

Male infertility is a global health problem, and the underlying molecular mechanisms are not clearly known. Ion channels and microRNAs (miRNAs), known to function in many vital functions in cells, have been shown to play a significant role in male infertility through changes in their expressions. The study aimed to evaluate the alterations of testicular and/or spermatozoal potassium voltage-gated channel subfamily J member 11 (KCNJ11), Cystic fibrosis transmembrane conductance regulator (CFTR), miR-let-7a and miR-27a expressions in carbamazepine-related male infertility. Here, we showed that carbamazepine reduced sperm motility, increased abnormal sperm morphology, and impaired hormonal balance as well as increased relative testis weight and decreased relative seminal vesicle weight. On the other hand, downregulated KCNJ11 and upregulated miR-let-7a expressions were determined in testis (p < .05). Also, downregulated KCNJ11 and upregulated CFTR and miR-27a expressions were found in spermatozoa (p < .05). Interestingly, altered testicular KCNJ11 and miR-let-7a expressions were correlated with decreased sperm motility and elevated sperm tail defect. Besides, spermatozoal CFTR and miR-27a expressions positively correlated with sperm tail defects. The results indicated a significant relationship between ion channel and/or miRNA expression alterations and impaired sperm parameters due to carbamazepine usage.     

Three Dimensions of Youth Social Capital and Their Impacts on Substance Use

Substance use is a threat to the health and well-being of youths, their families, and society as well. The literature shows that social interactions with peers, parents, and community may have an impact on adolescents’ behavior. Using data from the National Survey on Drug Use and Health of 2007, this study investigated the impact of social capital on youth behavior. The results show that peer influence is the strongest among the three significant predictors of substance use. While peer influence is positively correlated with substance use, family attachment and youth activities have a negative relationship with substance use. Findings demonstrate that there is a relationship between youth substance use and different aspects of social capital. By integrating different perspectives in social capital and substance use, this study successfully demonstrates how social capital can be utilized as a policy and intervention tool.